Finishing textile fabrics



Patented z, 1943' 'r'rmsnrnc 'mx'rnn memos arren c. MagilL'Jeifcr-sonvllle, ma, assignor to 1 Sears, Roebuck and C0,, Chicago, 111., a corporation of New York No Drawing. Application December 30, 1937,

Serial N0. 182,545

4 Claims.

My invention relates to the finishing of textile fabrics, and more especially. fabrics of cotton, linen, jute and cellulosic fibres generally, and artificial silk of cellulose derivatives, andhas as a special object the provision of a process for treating such fabrics whereby the fabric will be given a permanent finishv and will be preshrunken.

Fabrics treated in accordance with my invention have increased durability and a more attractive appearance as compared with untreated fab- I rics' and are substantially immune to shrinkage in subsequent laundering.

Another object of my'invention is to provide a process of the type referred to which will be more economical and more eilicient than previously.

known methods for accomplishing the same purposes and which will produce improved results.

Various other. objects and advantages will become apparent to those skilled in the art as the description proceeds.

I am aware that other methods have been suggested for treating fabrics, but I have found from a long and thorough study-thereof that said previously suggested methods in most cases, fail to produce the optimum results. Inasmuch as said treatments involve a wide variety of physical and chemical factors, a comparatively slight variation of one or-more of said factors is found to produce a great change in the final results, and in view ofthe close-inter-relation of. said results are not usually predictable.

The process which I have evolved has been arrived atafter extensive experimentation.

Example a 59 The following is given as an example of a process embodying my invention and should be considered as illustrative of thesame and not as limiting.

The cloth as it comes from the loom is singed,

desized, kier boiled, and framed back to substantially its original width. These treatments are individually well known in the art and need not be described in detail. is well known in the art, the singeing process removes the fuzzy fibres from the surface whichare always present as the fabric comes from the loom. tion, of course, removes the size present in the warp threads, while the kier boiling remotes the wax, pectin,-motes, etc., always Zpresent in cotton- The framing offsets the stretching caused by the preceding operations.

Thefabric, treated as above, after it .has bet 1 dried, is subjected to an aqueous bath of approx- 55 The desizing operati said factors,

imately 100 g. per liter of copper sulphate at temperature of about F., and it is allowed to remain in said bath until thoroughly impregnated or padded. This requires a maximum time of about one minute. The cloth, thus padded with copper sulphate is then passed into a bath made up approximately as follows:

Grams .per liter Caustic soda 125 Aqua ammonia (26%) The fabric is allowed to remain in this bath at a temperature of about 40 F. until the causticammonia has caused the filaments to swell, re-

. suiting in a rearrangement of the cellulose structure. This action should not be longer than about one minute.

The fabric, after removal from the causticammonla bath, is promptly rinsed in cold'water, say at room temperature or below, after which it is subjected with agitation to a bath of 6% sulphuric acid at about 90 F. for about 1/2 to 3 minutes. It lsthen thoroughly washed in cold water to remove all'acid, then run over a set of hot rolls to remove excess moisture, i. e., for damp drying the material, and then stentered on a hot frame preferably to about 2 inches less than its original greige width, in case a 40 inch greige material is used at the start. However, the material may be stentered up to approximately its original width. In any case, there is a substantial saving over known methods, wherein there is a high shrinkage loss and in methods wherein the r 35 greige width.

w The cold water rinse mentioned above removes the excess of chemicals from the previous treatmerits and the sulphuric acid thereafter promptly halts any reactions within the cellulosic fibres and tends. to deflate and set them. The slight shrinkage brought about by the last mentioned treatment is held by promptly drying and framing the goods while in the wet state.

It should be understood that the formulas given above apply to greige cotton sheeting within a range of, say, 2.85 to about 4.30 yards per pound; on other grades of material, the quantities of chemicals will vary substantially in proportion. Thus, on 80 square percale of weight approximately 5 yards per pound, the following concentrations would be used:

goods as a result of the treatment.

On a 2.20 denim fabric, approximately the following concentrations would be preferred:

The other conditions, such as temperatures, etc., would be the same as given above.

In all cases the width at which the goods are to be finished depends upon the potential shrinkage of the greige goods as well as their greige width.

Should a stiffer finish be desired, this may be obtained by increasing the amount of copper sulphate, say up to about and also by lowering the temperature of the caustic-ammonia bath. Independently of the concentration, a lower temperature of this bath greatly increases the stiffness produced in the fabric. At a temperature of about 0 F., a maximum stiifness is produced.

While my process is intended primarilyto be used on greige cotton before dyeing or printing, it can also be applied to dyed or printed fabrics and can be used on fabric of any width or construction.

My invention has many advantages, of which the following area few:

My improved process pre-shrinks' the goods and provides a pure, permanent finish which is not materially afiected by washing. The chemical baths which I employ are very stable and will not deteriorate on standing or during the use thereof in processing the 'goods.

An important advantage of my invention is that there is practically no working loss of the In other words, the goods suffer practically no loss in length. The stentering to slightly less than original width gives a very substantial increase in strength.

It has been found that dyeing and printing of goods treated in accordance with my finishing process requires approximately less dyestufi and other chemicals used for dyeing and printing than goods not treated in accordance with my invention.

Goods treated according to my invention will permanently retain their finish regardless of laundering. The fabric is not weakened by my on the contrary, is in many cases I do not wish to be limited to the specific embodiments and uses shown except to the extent indicated in the appended claims, which are to be interpreted as broadly as the state of the art will permit.

I claim:

1. A method of pre-shrinking and finishing cellulosic textile fabric, comprising subjecting the fabric to a copper sulphate bath having a concentration of about 100 g. per liter at about F. to pad the fibre, treating the padded material with an alkaline bath containing about g. per liter of ammonia and about g. per liter of caustic soda at about 40 F., rinsing out the excess alkali, and setting the fibre in a bath containing about 6% sulphuric acid at about 90 F., and washing out the excess acid.

2. A method of pre-shrinking and finishing cellulosic textile fabric, comprising treating the cloth to singeing, desizing, kier boiling and framing back to approximately its original width, subjecting the fabric to a copper sulphate bath having a concentration of about 100 g. per liter at about 90 F. to pad the fibre, treating the padded material with an alkaline bath containing about 100 g. per liter of ammonia and 125 g. per liter of caustic soda at about 40 F., rinsing out the excess alkali, setting the fibre in a bath' containing about 6% sulphuric acid at about 90 F., washing out the excess acid, and stentering to a width substantially less than the original width of the cloth.

3. A method of pre-shrinking and finishing cellulosic textile fabric, comprising padding the material in a copper sulphate bath of a concencellulosic textile fabric, consisting in padding the material in a copper sulphate bath having a concentration of about-100 to g. per liter, and passing the padded material through a solution containing approximately 125 to g. per liter of caustic soda and about 100 g. per liter of aquaammonia, the temperature of the baths and the time of treatment being so controlled that the fibers are not substantially solubilized, washing the material, souring, rewashing and stentering.

WARREN C. MAGILL. 

